That is perfectly acceptable and actually the whole purpose of the render section on Mecabricks. As long as users don’t take credits for the build, which he didn’t, this is ok. If really you only want people to look at it in the player and not open it in the workshop, you have an option to tick in the model preferences.

@Scrubs While I love the ability to render others' work and let them do the same, it might be nice if the owner of the model had the ability to remove renders on their model even by other people. This would of course rarely be needed, but it would be nice to be able to do if you greatly disliked a render 😃

No, the model belongs to the owner but not the images. Therefore only admins have this possibility. I may add a lock preference in the future for render upload.

The way I see it, when you upload a model, you're basically uploading the instructions to build your set out of actual physical LEGO bricks. If you just released the instructions, and then someone built their own set and took photos of them, that's a pretty normal occurrence in most communities.

So this is just that, but digitally.